Clinical outcomes of laparoscopic-assisted natural orifice specimen extraction colectomy using a Cai tube for left-sided colon cancer: a prospective randomized trial

Background The role of laparoscopic-assisted natural orifice specimen extraction (LA-NOSE) colectomy in the treatment of left-sided colon cancer has not been well defined, and there remains confusion about how to conveniently exteriorize specimens through natural orifices. Therefore, we introduced a homemade invention, the Cai tube, to facilitate the extraction of specimens and compared the clinical outcomes of LA-NOSE with conventional laparoscopic (CL) colectomy for left-sided colon cancer. Methods From March 2015 to August 2017, patients with left-sided colon cancer were randomly divided into LA-NOSE and CL groups. Specimens were extracted through the anus with the help of a Cai tube (Patent Number: ZL201410168748.2) in the LA-NOSE group. The primary outcome measure was postoperative pain. Secondary outcomes were the duration of operation, postoperative recovery, surgical morbidity, pathological quality of the specimen, and long-term outcomes, including 3-year overall survival, disease-free survival, local recurrence, and overall recurrence. Results A total of 60 patients (30 per group) were recruited for this study. None of the patients required emergency conversion to conventional laparoscopic or open surgery during the operation. The postoperative maximum pain score was significantly lower in the LA-NOSE group (mean 2.5 vs. 5.1, P = 0.001), as was the additional analgesia requirement (mean 2/30 vs. 10/30, P = 0.021). Patients in the LA-NOSE group experienced a shorter first time to passage of flatus (mean 2.2 vs. 3.1 days, P = 0.026). All patients could control their defecation at 6 months after surgery. The comparison between the two groups showed no significant differences in the operative time, bleeding volume, postoperative hospital stay, surgical morbidity rates, number of lymph nodes harvested, or resection margin status. The mean follow-up was 48 months (range 7-59) and was similar in both groups. The results showed no differences in long-term outcomes between the two groups. Conclusion In the treatment of left-sided colon cancer, compared with conventional laparoscopic colectomy, LA-NOSE colectomy using the Cai tube exhibited lower postoperative pain, shorter recovery of gastrointestinal function, and similar long-term outcomes. Registration number ChiCTR-OOR-15007060 (http://www.chictr.org.cn/).